Process of cleaning conveying and supporting elements



June 2, 1925. 1,540,454

J. T. AYERS I PROCESS or CLEANINQ CONVEYING AND SUPPORTING EIIJ'EMENTS Filed Feb 2 1920 /m//1f0/f John 7. flyers a] l l/ v o m m- Patented June 2, 1925.

UNITED STATEii 1,540,454 PATENT OFF-ICE.

JOHN T. AYERS, 0F LAGHUTE, QUEBEC, CANADA.

PROCESS OF CLEANING CONVEYING AND SUPPORTING ELEMENTS.

Application filed February 2, 1920. Serial No. 355,797.

To all whom it may concern:

Be it known that I, JOHN T. AYERs, a subject of'the King ofGrreat Britain, and resident of the town of Lachute, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Processes of Cleaning Conveying and Supporting Elements, of which the following is a full, clear, and exact description. v

This invention relates to improvements in a process or method of cleaning fabrics and particularly the felts of paper machines and the like, and the object of the invention is to-provide a method by which a paper machine felt or similar conveyor may be cleaned while in use in such a way that foreign matter is continuously removed and does not accumulate on the felt, necessitating removal of the felt from the machine.

The process consists briefly in passing the felt in contact with a napping element, which loosens or tears off particles or masses of foreign matter adhering to the surface. The felt then passes adjacent a spraying device, which directs a cleaning fluid at high velocity against the back of the felt so as to further loosen or drive out foreign matter on the face. At the same time, the face of the felt is passed over a suction box which collects the cleaning fluid and practically completes the removal of foreign matter. The felt finally passes over a final suction box, which removes any foreign matter not previously removed and also extracts what remains of the cleaning fluid.

In the accompanying drawing in which apparatus for carrying out the process is diagrammatically illustrated, 11 designates the felt of a paper machine having a working face 12 or may designate any fabric which it is desired to clean. This felt is passed conveniently face down over a brushing roll 13, which is driven by some positive means, such as a belt 14, or by the felt itself. The one essential of this step of the process is that the surface speed of the brushing device must be different from the surface speed of the felt. Preferably, the surface speed of the brushing element is greater than the surface speed of the felt and the roll is driven independently of the felt. The surface speed of the roll may, however, be lower than the surface speed of the felt and the roll be driven either by an independent drive or by the felt. When the roll is driven by the. felt, it is necessary to p'rovlde a brake to keep the surface speed of the roll below the surface speed of the felt. The

napping element tears off or loosens from the working surface of the felt accumulations of foreign matter and also works or opens up the surface of the fabric, which has been matted by use, so that a cleansing fluid may pass freely through.

After completion of the brushing step, the felt passes adjacent a conduit 15 from which cleaning fluid is directed in small jets at highvelocity against the fabric. Preferably, the velocity of the jets is suflicient to carry the fluid through or nearly through the fabric. When cleaning paper machine felts or the like, the cleaning fluid is directed againstthe back of the felt, so as to emerge at the face thereof andcarry out the particles of foreign matter loosened by the brushing action. Obviously, if these jets were directed against the working face of the felt, they would tend to bed the foreign matter deeper into the felt. Associated with the conduit 1.5 is a suctionbox 16, over which a given portion of the felt passes, while it is being sprayed with'cleaning fluid. The actionof the suction box is to assist the passage of the cleaning fluid through the felt and also to gather the fluid and foreign matter washed out of the felt. This feature of gathering the cleaning fluid without allowing it to escape into the air is especially important if the fluid is steam or a hot liquid, as it prevents the surrounding air from being filled with vapor. When a liquid at ordinary temperatures is used, a simple trough will suffice to collect the same but, unless suction is employed, the removal of foreign matter is not so satisfactory, other things being equal. The face of the felt passes preferably but not necessarily in contact with the suction box.

After the spraying and suction, the felt is subjected to a further suction and driving action by passing it over a second suction box 17. The amounts of suction maintained in the two boxes may be equal or may be greater in either box, but preferably greater in the box 17 The suction in the second box serves principally to extract the cleaning fluid from the felt and thus to dry the same. This second suction box also serves to draw out of the felt foreign matter which has not been previously removed. Obviously, the best results are obtained by passing the face of the felt in contact With the suction boxes. The successive brushing, Washing and drying actions to which the felt has been. subjected have the effect in most cases of so renovating the surface that the proper nap or finish is restored. If necessary, however,

the face of the felt maybe treaded to a fur ther brushing or carding operation.

lVhile the invention has been described particularly in relationtoits specific application to, cleaning paper machine felts,'it will be understood that it may be" used equally ell for cleaning fabrics of other descriptions. It Will alsob'e understood that in such cleaning operations, either or. both ofthe preliminary and final brushing steps may not be necessary.

In the application of the process to paper machine felts, the various elements forcarrying out thedifleltent steps of the processhave been illustrated as arranged together and Without any relation to a paper machine in which the felt operates. It will be, under stood that the invention is not limited to the relative positions of the elements to one an: other or to a paper or other machine nor to the relative sequence of the steps. It will also be understood that the elements may be located all together at convenient points in a paper or other machine. In other words, the felt of a paper machine or the like may be. subjected to the cleaning operations of this process. all at one place in a machine or at different remote points in the machine and in any sequence-de'sired' It will: thus be seen that according to this process the felt of a paper machine may be cleaned continuously While in operation in fabrim'and applying suction to. the opposite surface, and the drying. being effected by drawing out cleaning fluid from the fabric and drawing air through the fabric.

2. A process of cleaning paper machine felts and the like, which comprises subjecting the felt to a brushing action by passing it verr -ll h v ng a u fa spe ddifi r from the surface speed ofthe felt, then subiecti g t he j t of aning fl pp i d to one surface and to suction appliedto the other-surface. 1

A p o s f rewrit n Paper ma ne l W ile n Ope tion, whi h on sts in ubj ng the e t m. as in and ry operation by directing ets, of cleaning fluids ag i e siirif ceef he elt andv apply n u n s multa e u ly. t e pp it u ac f h fe t t t pa nt of replic tio rhe. cleaning f u d w drew eu he d r nd then applying. a subsequent drying opera-, er by'drav a thr ugh the e tn Wi ness w ereof, I ha e h unt s my hand- J HN AYERS- 

